Silicon nutrition promotes root growth and tissue mechanical strength insymbiotic cowpea

2003 ◽  
Vol 30 (9) ◽  
pp. 947 ◽  
Author(s):  
Felix D. Dakora ◽  
Aziwe Nelwamondo
Keyword(s):  
Root Growth ◽  
Mechanical Strength ◽  
Shoot Growth ◽  
Lateral Roots ◽  
Reproductive Structures ◽  
Root Shoot Ratio ◽  
Hormonal Signal ◽  
Silicon Nutrition ◽  
Hydroponically Grown ◽  
Aba Biosynthesis

Application of metasilicic acid (0, 0.04, 0.08, 0.20, 0.40 or 0.80 g L–1) to hydroponically-grown, Bradyrhizobium-infected cowpea [Vigna unguiculata (L.) Walp.] plants showed an increased assimilation of silicon into roots and shoots, which triggered a significant (P<0.05) promotion of root growth, but not shoot growth. Root : shoot ratio therefore, increased markedly (P<0.05) with higher metasilicate application. Mechanical strength of stems and peduncles also increased significantly (P<0.05) with silicon nutrition compared with control plants receiving no metasilicate. But the mechanical strength of roots was not affected. Radioimmunoassay of lateral roots, free of nodules, from plants fed metasilicate revealed markedly (P<0.05) increased concentrations of endogenous ABA, a hormonal signal that stimulates root growth. In contrast, a decreasing concentration of the cytokinin zeatin ribose was obtained with increasing metasilicate supply. These data show that silicon nutrition in symbiotic cowpea promotes an increase in mechanical strength of stems, which bear the entire weight of shoots, and peduncles, which, in turn, support weighty reproductive structures including developing pods and seeds. The increased concentration of ABA in roots as a result of improved silicon nutrition suggests that this element might be an elicitor of ABA biosynthesis and / or its accumulation, which then affected lateral root growth in this study.

scholarly journals Root and Shoot Growth Periodicity of Green Ash, Scarlet Oak, Turkish Hazelnut, and Tree Lilac

1995 ◽  
Vol 120 (2) ◽  
pp. 211-216 ◽  
Author(s):  
J. Roger Harris ◽  
Nina L. Bassuk ◽  
Richard W. Zobel ◽  
Thomas H. Whitlow
Keyword(s):  
Root Growth ◽  
Root Length ◽  
Shoot Growth ◽  
Lateral Roots ◽  
Growth Patterns ◽  
Extension Rate ◽  
Green Ash ◽  
Growth Measurement ◽  
Root And Shoot Growth ◽  
Growth Periodicity

The objectives of this study were to determine root and shoot growth periodicity for established Fraxinus pennsylvanica Marsh. (green ash), Quercus coccinea Muenchh. (scarlet oak), Corylus colurna L. (Turkish hazelnut), and Syringa reticulata (Blume) Hara `Ivory Silk' (tree lilac) trees and to evaluate three methods of root growth periodicity measurement. Two methods were evaluated using a rhizotron. One method measured the extension rate (RE) ofindividual roots, and the second method measured change in root length (RL) against an observation grid. A third method, using periodic counts of new roots present on minirhizotrons (MR), was also evaluated. RE showed the least variability among individual trees. Shoot growth began before or simultaneously with the beginning of root growth for all species with all root growth measurement methods. All species had concurrent shoot and root growth, and no distinct alternating growth patterns were evident when root growth was measured by RE. Alternating root and shoot growth was evident, however, when root growth was measured by RL and MR. RE measured extension rate of larger diameter lateral roots, RL measured increase in root length of all diameter lateral roots and MR measured new root count of all sizes of lateral and vertical roots. Root growth periodicity patterns differed with the measurement method and the types of roots measured.

Effect of ozone and aluminum on pitch pine (Pinusrigida) seedlings: growth and nutrient relations

1990 ◽  
Vol 20 (11) ◽  
pp. 1714-1719 ◽  
Author(s):  
George A. Schier ◽  
Carolyn J. McQuattie ◽  
Keith F. Jensen
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Mycorrhizal Fungus ◽  
Mineral Elements ◽  
Growth Effect ◽  
Solution Ph ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Pitch Pine ◽  
Nutrient Relations

Newly germimated pitch pine (Pinusrigida Mill.) seedlings inoculated with a mycorrhizal fungus (Pisolithustinctorius (Pers.) Coker & Couch) were grown for 13 weeks in sand irrigated with nutrient solution (pH 4.0) containing 0, 12.5, 25, 50, or 100 mg/L of aluminum (Al) in growth chambers fumigated with 0, 50, 100, or 200 ppb ozone. Increasing the concentration of ozone or Al caused increasing reductions in needle length, seedling height, and biomass of needles, stems, and roots. Significant ozone × Al interactions indicated that ozone and Al were interacting synergistically in reducing growth. Effect of treatments on the root/shoot ratio demonstrated that shoot growth was more sensitive to Al than root growth, whereas root growth was more sensitive to ozone. The concentration of most mineral elements (P, K, Ca, Mg, Mn, Cu, Zn) in needles was reduced by ozone or Al. Iron was the only element that increased with increasing concentrations of ozone or Al.

Effect of Naptalam on Chloramben Toxicity, Uptake, Translocation, and Metabolism in Cucumber (Cucumis sativus)

Weed Science ◽  
1991 ◽  
Vol 39 (1) ◽  
pp. 27-32
Author(s):  
Larry D. Knerr ◽  
Herbert J. Hopen ◽  
Nelson E. Balke
Keyword(s):  
Root Growth ◽  
Cucumis Sativus ◽  
Shoot Growth ◽  
Petri Dish ◽  
Dry Weight ◽  
Laboratory Studies ◽  
Cucumber Seedlings ◽  
Plant Parts ◽  
Cucumber Roots ◽  
Hydroponically Grown

Laboratory studies demonstrated that naptalam safens cucumber against the phytotoxic effects of chloramben. In petri dish studies, cucumber seedlings grown from seeds exposed to chloramben plus naptalam had greater shoot growth, root growth, and dry weight than seedlings grown from seeds exposed to chloramben alone. Naptalam also partially reversed the reduction in dry weight of various plant parts caused by exposure of roots of hydroponically grown seedlings to chloramben. More radioactivity from root-applied14C-chloramben remained in cucumber roots and less was translocated to shoots with a14C-chloramben plus naptalam treatment than with a14C-chloramben alone treatment. Naptalam appeared to influence chloramben metabolism. In various plant parts, concentrations of chloramben and its metabolites differed between the two treatments.

scholarly journals Tree Root Growth and Development. I. Form, Spread, Depth and Periodicity

1990 ◽  
Vol 8 (4) ◽  
pp. 215-220 ◽  
Author(s):  
Edward F. Gilman
Keyword(s):  
Moisture Content ◽  
Root Growth ◽  
Fine Roots ◽  
Growth And Development ◽  
Shoot Growth ◽  
Lateral Roots ◽  
Soil Characteristics ◽  
Soil Conditions ◽  
Urban Landscapes ◽  
Root Growth And Development

Abstract Root form is governed by seedling genetics and soil characteristics including texture, compaction, depth to the water table, fertility, moisture content and other factors. Trees develop lateral roots growing parallel to the surface of the soil. These are generally located in the top 30 cm (12 in) of soil. Fine roots emerge from lateral roots and grow into the soil close to the surface. If soil conditions permit, some trees grow tap and other vertically oriented roots capable of penetrating several feet into the soil. Many trees, particularly those planted in urban landscapes, do not generate tap roots. Lateral roots spread to well beyond the edge of the branches. Their growth in governed by competition from other plants, available water, soil temperature, fertility, stage of shoot growth and other factors.

Root growth and root growth capacity of white spruce (Piceaglauca (Moench) Voss) seedlings

1985 ◽  
Vol 15 (4) ◽  
pp. 625-630 ◽  
Author(s):  
Anne M. Johnson-Flanagan ◽  
John N. Owens
Keyword(s):  
Root Growth ◽  
Root Elongation ◽  
Shoot Growth ◽  
Lateral Roots ◽  
White Spruce ◽  
Shoot Elongation ◽  
Growth Capacity ◽  
Root Growth Capacity ◽  
Root And Shoot Growth

Root growth in the root systems of Styroplug-grown white spruce (Piceaglauca (Moench) Voss) seedlings increases in the spring before shoot elongation and again in the fall after bud development is complete. This is followed by root dormancy and quiescence, which are distinguished on the basis of ability to elongate under root growth capacity (RGC) conditions. The number of white long lateral roots produced during RGC tests correlated significantly with the number of white long lateral roots under lathhouse conditions. Increased mitotic activity is required for root elongation. However, mitotic frequencies could not be used to assess RGC because of the confounding effects of independent growth cycles in individual roots. Cell expansion and transformation of insoluble carbohydrates are important controls of root elongation. The relationship between root and shoot growth under RGC conditions may not support the role of shoot elongation in decreasing root elongation. Conversely, this may indicate that RGC tests alter the endogenous controls of root and shoot growth.

scholarly journals Survival and Growth of Transplanted Orchid Seedlings Enhanced by DCPTA

HortScience ◽  
1991 ◽  
Vol 26 (10) ◽  
pp. 1284-1286 ◽  
Author(s):  
James H. Keithly ◽  
Daniel P. Jones ◽  
Henry Yokoyama
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Fold Increase ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Survival And Growth

The growth-enhancing property of DCPTA was tested on transplanted seedlings of Brassolaeliocattleya × Hort. (Blc. Bryce Canyon × Lc. Pirate King), Dendrobium × Blume. Hickham Deb, Epidendrum radicans Pav. ex Lindl., Lueliocattleya × Rolfe Prism Palette `The Clown', and Phalaenopsis × Blume. [Pink Zebra × (Jutta Brungor × Music)]. After 3 to 6 months of greenhouse growth, plants treated with 30 μm DCPTA produced a 2- to 3-fold increase in root growth compared to the controls. Shoot growth, root: shoot ratio, and the survival of DCPTA-treated plants were increased significantly when compared with controls. Chemical name used: 2-(3,4-dichlorophenoxy)triethylamine (DCPTA).

Root and shoot growth by seedlings of annual and perennial medic, and annual and perennial wheat

2011 ◽  
Vol 62 (5) ◽  
pp. 367 ◽  
Author(s):  
P. R. Ward ◽  
J. A. Palta ◽  
H. A. Waddell
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Climatic Conditions ◽  
Shoot Biomass ◽  
Growth Stages ◽  
Seedling Vigour ◽  
Leaf Stage ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Perennial Wheat

Perennial plants such as lucerne are now widely acknowledged as one means of controlling the expansion of dryland salinity in southern Australia. However, their inclusion in farming systems is limited by poor seedling vigour, thought to be associated with greater allocation of biomass to perennating organs in roots, and poor adaptation to some soils and climatic conditions in south-western Australia. For this reason, interest in other perennial options such as perennial wheat is increasing. In this research we compared early (29-day) seedling growth and root : shoot ratios for annual and perennial medics (Medicago truncatula and M. sativa), and for annual and perennial wheat (Triticum aestivum and Triticum × Agropyron cross). For the medics, the annual reached the 6-leaf stage after 29 days and produced more root and shoot biomass than lucerne (4-leaf stage after 29 days), but there was no difference in root : shoot ratio or depth of root growth. For wheat, there were no differences in root growth, shoot growth, or root : shoot ratio between the annual and perennial lines (Zadoks growth stages 23 and 21, respectively, after 29 days). The poor competitive performance of M. sativa seedlings relative to M. truncatula was not due to changed allocation of biomass to shoots, but was related more to seed size (2.7 and 5.0 mg, respectively). This does not seem to occur to the same extent in perennial wheat lines, suggesting that their seedling performance may be more competitive.

Understanding the root sink.

2022 ◽  
pp. 59-66
Author(s):  
T. M. DeJong
Keyword(s):  
Root Growth ◽  
Root Development ◽  
Apical Meristem ◽  
Shoot Growth ◽  
Lateral Roots ◽  
Fruit Trees ◽  
Extension Growth ◽  
Factors Affecting ◽  
And Function ◽  
Shoot Meristems

Abstract Root development and growth is similar to shoot growth in that extension growth is initiated by an apical meristem and girth growth of mature roots is carried out by the vascular cambium. However, the initiation of lateral roots is entirely different than the initiation of lateral leaves or shoot meristems. This chapter deals with understanding the root sink in fruit trees by studying root growth, including the initiation of lateral roots, root classification according to size and function, factors affecting their growth, and rootstocks.

Effects of Single-seed Sowing on Root Growth, Root-shoot Ratio, and Yield inPeanut (Arachis hypogacaL.)

2013 ◽  
Vol 39 (12) ◽  
pp. 2228 ◽  
Author(s):  
Ye FENG ◽  
Feng GUO ◽  
Bao-Long LI ◽  
Jing-Jing MENG ◽  
Xin-Guo LI ◽  
...  
Keyword(s):  
Root Growth ◽  
Single Seed ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Seed Sowing

Foliar vs. Root Sensitivity of Hairy Bittercress (Cardamine hirsuta) to Isoxaben

2006 ◽  
Vol 20 (2) ◽  
pp. 326-333 ◽  
Author(s):  
Glenn Wehtje ◽  
Charles H. Gilliam ◽  
Michael E. Miller ◽  
James E. Altland
Keyword(s):  
Root Growth ◽  
Environmental Conditions ◽  
Day Length ◽  
Root Growth Inhibition ◽  
Root Absorption ◽  
Nursery Production ◽  
Plant Maturity ◽  
Higher Temperature ◽  
Inhibit Root Growth ◽  
Hydroponically Grown

It has been previously reported that POST-applied isoxaben can effectively control established hairy bittercress. Experiments were conducted to determine the relative importance of root vs. foliar entry of POST-applied isoxaben. At a common isoxaben rate of 0.56 kg/ha, foliar-only and foliar plus soil applications provided 10.5 and 23.3% control, respectively, as determined by fresh weight reduction. In contrast, soil-only application provided 47.0% control. Hairy bittercress foliar absorption of14C–isoxaben did not exceed 15% of the amount applied after 72 h. Therefore, the comparatively less effectiveness of foliar-only applications may be attributed primarily to limited absorption. Minimal isoxaben concentration required to inhibit root growth of hydroponically grown hairy bittercress was 0.0025 mg/L. Higher concentrations were required to produce a response in the foliage. Sorption of isoxaben by pine bark rooting substrate, typical of what is used in container nursery production, exceeded 99% of amount applied after 36 h. Even with 99% sorption, the probable concentration within the aqueous phase remains sufficient to inhibit hairy bittercress root growth. Additional studies with14C–isoxaben established that approximately 35% of the root-absorbed isoxaben was translocated into the foliage. Translocation from the roots into the foliage was reduced to 16% when the experiment was repeated during environmental conditions less favorable for vegetative growth (i.e., longer day length and higher temperature). Results indicate that the control of hairy bittercress with POST-applied isoxaben is likely the result of root absorption and root-growth inhibition. Expression of phytotoxicity within the foliage is also a component, but is dependent upon the root-absorbed isoxaben being translocated into the foliage. Extent of this translocation is dependent upon plant maturity and prevalent environmental conditions.

Sign in / Sign up

Export Citation Format

Share Document